Many types of hardware are available both for the fixation of bones that are fractured and for the fixation of bones that are to be fused. A fusion is an operation where two bones, usually separated by a joint, are allowed to grow together into one bone. The medical term for this type of fusion procedure is arthrodesis.
For example, lumbar fusion procedures have been used in the treatment of pain and the effects of degenerative changes in the lower back. An example of a lumbar fusion is a fusion in the S1-L5-L4 region in the spine.
Another example, the human hip girdle (see FIGS. 9 and 10) is made up of three large bones joined by two relatively immobile joints. One of the bones is called the sacrum and it lies at the bottom of the lumbar spine, where it connects with the L5 vertebra. The other two bones are commonly called “hip bones” and are technically referred to as the right ilium and the left ilium. The sacrum connects with both hip bones at the left and right sacroiliac joints (in shorthand, the SI-Joint).
The SI-Joint functions in the transmission of forces from the spine to the lower extremities, and vice-versa. The SI-Joint has been described as a pain generator for up to 22% of lower back pain.
To relieve pain generated from the SI Joint, sacroiliac joint fusion is typically indicated as a surgical treatment, e.g., for degenerative sacroiliitis, inflammatory sacroiliitis, iatrogenic instability of the sacroiliac joint, osteitis condensans ilii, or traumatic fracture dislocation of the pelvis. Currently, screws and screws with plates are used for sacro-iliac fusion. At the same time the cartilage has to be removed from the “synovial joint” portion of the SI joint. This requires a large incision to approach the damaged, subluxed, dislocated, fractured, or degenerative joint.
There is a need for improved bone fusion treatments for addressing chronic hip, joint or back pain.